The five were thwarted by overt and covert operations by garda units with the aid of criminal intelligence.

Assistant Garda Commissioner Michael O'Sullivan, who is currently in charge of drugs and organised crime bureau, said there was no criminal gang which stood the test of time.

"Eventually, their members, both at high and low levels, are arrested and their empire falls apart.

"Criminal history over the past 20 years shows that gangs come and gangs go. They fall apart and their members are arrested", Assistant Commissioner O'Sullivan said.

The gardai either arrested them here or had them arrested abroad and officers then try to either dissolve or dismantle their operations.

There were several cases where peoples' lives had been saved through pro-active policing operations and, in some of those, the details had not made the newspapers because of the nature of the garda operation.

Asked about the level of garda intelligence in relation to the Christy Kinahan crime cartel, which has been blamed for six of the seven gangland feud murders since September, he said the gardai had been investigating that gang since September 1986.

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This investigation had resulted in the seizure of drug shipments with a value of millions of euro as well as properties worth millions or euros also, as well as the arrest and jailing of a number of prominent criminals.

Mr O'Sullivan argued that there were a lot of people in jail, who wished that garda intelligence was not as good as it was.

"Nobody is beyond the law. Nobody is invincible", he added.

"When you look at criminal organisations over the years, you see they have a tendency to implode and former associates try to kill each other.

"We are constantly on alert to try to save lives", he said.

Commenting on the setting up of the new garda crime task force, he said this would not be a question or robbing Peter to pay Paul and said the force had the resources to man the new unit.

"Its a matter of re-prioritising. There may not be a lot of money available but resources are not a problem", he said.

Meanwhile, Tanaiste and Justice Minister Frances Fitzgerald announced at the Garda College in Templemore today that an additional allocation of €55m was being made available for the rest of the year, including the 5m allocated in February to fund garda operations.

She said this decision ensured the gardai had the necessary financial resources to face down the appalling and ruthless cycle of violence, caused by organised crime, and continue the successful crackdown on rural crime and burglaries.